[[quoteright:320:http://static.tvtropes.org/pmwiki/pub/images/Sonic_3D_start_001_6481.png]]
[[caption-width-right:320:[[TagLine Blue is back!]]]]

An isometric {{platformer}} known in North America as ''[[MarketBasedTitle Sonic 3D Blast]]'', starring Creator/{{Sega}}'s [[Franchise/SonicTheHedgehog three-foot speed demon]], developed by Creator/TravellersTales. The game was released for the [[UsefulNotes/SegaGenesis Sega Mega Drive/Genesis]] and the UsefulNotes/SegaSaturn (to compensate for the cancellation of the game that was supposed to be the Saturn's KillerApp, ''Sonic X-treme'') in 1996, as well as for the UsefulNotes/MicrosoftWindows in 1997. It was initially passed up for release in Japan until 1999, where the Saturn version's release coincided with ''VideoGame/SonicAdventure [[UpdatedRerelease International]]''. The Mega Drive version was the last brand new Sonic release for that system and second-last overall in North America, after the 1997 compilation ''Sonic Classics 3-in-1'' (which was previously released in Europe in 1995).

Remember that little blue bird that Franchise/SonicTheHedgehog freed out of robot shells in the [[VideoGame/SonicTheHedgehog original]] [[VideoGame/SonicTheHedgehog2 16-bit]] [[VideoGame/Sonic3AndKnuckles trilogy]], the Flicky? It turns out they reside on Flicky Island, where they can travel through dimensions via giant rings. Learning about this, Dr. Robotnik has decided to invade the island and trap its inhabitants inside his Badnik army, that he can seize the seven Chaos Emeralds and {{take over the world}}.

During his usual [[WalkTheEarth nomadic routine]], Sonic pays a visit to his little pals on Flicky Island, only to discover they've all been imprisoned in Badnik shells. Now, our true blue hero must free his friends and stop Robotnik once again.

As noted above, ''Sonic 3D'' is an [[IsometricProjection isometric]] platformer (with nifty pre-rendered 3D sprites), but that's not the only difference in gameplay. Beating an act is not done by reaching the goal as soon as you can; instead, you have to collect a set of five Flickies and bring them to a giant Dimension Ring; there are usually two or three Dimension Rings, and once you successfully deposit each set, you beat the act. The only acts exempt from Flicky collect-a-thons are boss acts and an act near the end of the game which plays like a classic Sonic stage.

The Saturn version somewhat rectifies the control issues by offering the analog pad as an alternative to the D-Pad, as well as included a CD-quality soundtrack composed by Richard Jacques, additional graphical environmental effects such as fog and rain, and a polygonal Special Stage; but it lacks a save game feature (despite being on a system with a memory card-esque feature) and has [[LoadsandLoadsofLoading unusually long loading times]]. The PC port includes Jacques' soundtrack and a save game feature, but lacks some of the Saturn version's more noteworthy features such as the polygonal Special Stage and weather enhancements.

Not to be confused with ''VideoGame/SonicBlast'' for the UsefulNotes/GameGear, though the games were marketed together in commercials. Also unrelated to ''VideoGame/SonicTheHedgehog3''.
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!! This game provides examples of:

* AlliterativeName: All of the zone names.[[note]]This includes "The Final Fight" in the Mega Drive version, though this is instead known as "The Final Boss" in the Saturn and PC versions, which was actually the zone's WorkingTitle.[[/note]]
** With the exception of Gene Gadget Zone, which uses two different "G" sounds (/dʒ/ and /ɡ/).
* ArtEvolution: [[http://www.sonic.wikia.com/wiki/Sonic_3D_Blast/Gallery#2D_Artwork Check out the artwork made exclusively for the Sega Saturn release in Japan]] - the style looks like a lot like the missing link between the "classic" and "modern" character designs.
* BrutalBonusLevel: In the Mega Drive version, Knuckles' Special Stages are quite easy. Tails' Special Stages, in contrast, are much more difficult due to the sheer abundance of spiked balls combined with the fast pacing and frequent twists and turns. In the Saturn and PC versions, both characters share identical Special Stages, and only one gives you an Emerald per act (a OneUp will be rewarded in the other character's stage on the same act).
* ColourCodedForYourConvenience: Each of the four Flickies are color-coded as an indication of their movement patterns:
** '''Blue Flickies''' will make a conscious effort to find Sonic, and will wander around in a tight circle if they can't find him, making them easy to catch.
** '''Pink Flickies''' behave like blue ones, but they fly around in bigger circles.
** '''Red Flickies''' constantly jump high back and forth between two close points, not making any effort to find Sonic, making them hard to catch.
** '''Green Flickies''' wander around aimlessly with no interest in finding Sonic, even sometimes appearing to try to avoid him.
* ComicBookAdaptation: Franchise/ArchieComics published a 48-page special featuring a story based on the game's plot, while Fleetway's ''Comicbook/SonicTheComic'' did a very loose adaptation in issues 104-106.
* ConveyorBeltODoom: The setting for the Gene Gadget Zone boss.
* DemotedToExtra: Tails and Knuckles make cameos throughout the levels and let you access the Special Stage, but they have no role in the plot (such as it is) you don't get to play as them.
* DimensionalTraveler: The Flickies in this game come from another dimension. They come to Flicky Island via Dimension Rings for food.
* EternalEngine: Gene Gadget Zone and Panic Puppet Zone.
* ExcusePlot: Robotnik is kidnapping innocent Flickies! Guess who has to save the day?
* GameMod: ''Sonic 3D: No Flickies'' is a [=ROM=] hack of the game that, true to its name, redesigns the game so that you don't have to collect Flickies and can just blaze through the levels like in the original sidescroller games, with the Dimension Rings just serving as Checkpoints. Obviously, it makes the game a lot quicker and easier. A later mod even gives Sonic the ability to turn into [[SuperMode Super Sonic]] if all of the Chaos Emeralds are obtained.
* GreenHillZone: Green Grove Zone.
* HarmlessFreezing: Whereas [[VideoGame/SonicTheHedgehogCD previous]] [[VideoGame/Sonic3AndKnuckles games]] averted this, this game plays it straight in Diamond Dust Zone. You're even required to be frozen to advance through an automated section.
* InCaseOfBossFightBreakGlass: All of the end of level battles with Robotnik until Panic Puppet Zone Act 3, where flashing lights become the new target due to not being able to hit his cockpit directly (you hit the torso of the TrueFinalBoss if you can reach his level).
* {{Leitmotif}}: In the Saturn/PC version, Robotnik's normal theme is remixed into something more epic and sinister for the final boss music. It also briefly resurges in the BadEnding.
* LethalLavaLand: Volcano Valley Zone, complete with leaping fireballs and collapsing stone bridges.
* LoadsAndLoadsOfLoading: The loading times for the Sega Saturn version can run for as long as 30 seconds. This was slightly shortened in the Japanese release, and substantially improved in the PC port.
* MultipleEndings: Didn't get all the Emeralds? Well then you get the BadEnding, which alludes to Robotnik returning. Get them all? Then you gain access to The Final Fight, which is pretty self explanatory, and if you beat it, you get the GoodEnding.
* OurFounder: In Panic Puppet Zone Act 2, Sonic has to reach the top of a giant Robotnik statue through his nose. The boss fight for the stage takes place inside the statue.
* PowerUpLetdown: The Power Sneakers are not very useful in this game. They make Sonic, already slippery moving as is, very hard to control and it makes it easy for him to collide into an enemy or obstacle by accident. The open ended nature of the gameplay and lack of time limit also contradict the whole point of the powerup--helping you get to the end of the level faster.
* PointOfNoReturn: The final non-boss act of the game, Panic Puppet Zone Act 2, is a straight Sonic stage with no Flickies, and several points exist in the stage to prevent Sonic backtracking, but the most notable one is at the end of the stage, where you cross several plates that fall below you. After the second one, you're left with no choice but to enter the pipe in Robotnik's nose, which ends the stage and takes you to Panic Puppet Zone Act 3, a three-phase boss fight against three separate big-armed machines (if you have all the Chaos Emeralds, The Final Fight, which is in its own stage, follows Panic Puppet Zone Act 3).
* RecurringRiff: The Saturn/PC soundtrack incorporates the title theme melody into nearly every single track in the game.
* RuinsForRuinsSake: Rusty Ruin Zone.
* SingleUseShield: There are basic Blue Shield and Red Shield power-ups, the latter of which protects against fire and lava but doesn't enable the Fireball Spin Dash like the original Flame Shield from ''Sonic3AndKnuckles''. Instead, a midair homing ability called the Blast Attack was instead redistributed into the new Gold Shield, which is a predecessor to the Homing Attack seen in ''VideoGame/SonicAdventure''.
* SlippySlideyIceWorld: Diamond Dust Zone.
* SpiritualSuccessor: To the ''VideoGame/{{Flicky}}'' arcade game, which also revolved around guiding small bird creatures to a goal while avoiding enemies.
* TacticalSuicideBoss: The TrueFinalBoss (see below). The only time you can damage the final weapon is by hitting it when it briefly enters the platform Sonic is standing on. It will do this on every phase (you have to hit it to advance to the next phase and you have to go through each phase twice). Particularly egregious on the third phase (where you must dodge its spiked hands), as the ship isn't visible at the platform like it is on the other phases. The only time you see the boss on this phase is when it shows up for the sole purpose of being smacked and advancing the battle.
* TrueFinalBoss: The Final Fight, the [[FinalBoss Final]] BossBattle is available by beating the game with all the Chaos Emeralds, beating this boss is needed to get the GoodEnding.
* UnexpectedGameplayChange: The entire game involves destroying Badniks to free Flickies. But then Panic Puppet Zone comes. Act 1 has you freeing them in pods. Act 2 lacks them entirely, being a traditional Point A to Point B stage. The manual [[HandWave handwaves]] it by saying that Robotnik hasn't had time to put them in the Badniks yet as Sonic got there sooner than expected.
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